A dot in space and chromosomes

By Grant Jacobs 17/10/2010

Finally I offer some pictures in response to Alison. (I’m procrastinating, avoiding washing last night’s dishes for a little longer… C’mon now, don’t look at me like that. It’s Sunday.)

Alison challenged me last Friday week to put up a stunning science picture to beat her offering. Trouble is, what she offered to way too good to beat! It has everything you want. Self-explanatory, dramatic with great detail.

I searched for ages, and found it’s one thing to stumble onto these and another to go looking for them… then thought ’Stuff this, I’m going to put up something old and classical instead.’

Pale blue dot - the earth from 6.1 billion kilometres (Source: Wikimedia Commons.)
Pale blue dot - the earth from 6.1 billion kilometres (Source: Wikimedia Commons.)

The image to the left is so classic even it’s title is famous, Pale Blue Dot.

Legend – I’d write story, but it’s passed into legend by now – is that famous science communicator and astronomer Carl Sagan asked if those running the Voyager space mission would turn a craft around once it had completed it’s main mission, point the camera back at the earth, and take a shot.

The tiny blue dot about two-thirds down the bright band in the right part of the image is the earth from 6.1 billion kilometres.

It is a little abstract in some ways, but it shows the earth as this tiny mote in the vastness of space, and that’s only our tiny corner of space.

The Voyager craft were something that impressed the hell out of me as kid, swinging by all those planets. I remember the National Geographic stories with their photographs.

They’re still out there. Late July this year Voyager 2 had logged 12,000 continuous days of operation and it still sending back data (at 160 bits/second), used, for example to report the presence of strong magnetic field just outside the solar system.

Today you can follow their progress on twitter. As I write the Voyager 2 twitter feed reports

I am currently 12 hrs 58 mins 22 secs of light-travel time from Earth

Given a speed of light of approximately 299792 km/second, that’s very roughly 14 billion kilometres from earth. My head is doing rendition of the line ’It’s a Long Way to Tipperary …’

If that isn’t impressive enough, it’s travelled 21 billion kilometres to get there.

Mitotic chromosomes (via: The Pavellas Perspective)
Mitotic chromosomes (via: The Pavellas Perspective)

The second image, to the right, probably makes me a fuddy-duddy, but I like it for being a humble image of chromosomes.

I’m interested (among far too many other things) in the higher-order structure of chromosomes and how that relates to how genes are controlled.

This electron micrograph hides the complex detail; I like it’s peaceful simplicity, and how it shows chromosomes to be three-dimensional, rather than the flat cartoon sketches too often used in textbooks.

OK, OK. Now I’ll go and wash the dishes. Sigh.


I considered structure of protein complexes, some of which are truly stunning. Maybe I’ll do that some other time. The trouble is that these really want the story explaining them. There are also some excellent models of larger complexes of molecules. (I posted a model of the cytoplasm some time ago; see the first link, below.)

The source of the second image reminds me that I never did write about cochlear implants as I meant to almost a year ago now. (Sigh.)

I did also write some thoughts on the ‘miracles’ of the new Catholic saints, but the two really don’t sit together well!

Science on Code for life:

Friday picture: molecular modelling of the cytoplasm

The roots of bioinformatics

Loops to tie a knot in proteins?

Coiling bacterial DNA

Temperature-induced hearing loss

I remember because my DNA was methylated

0 Responses to “A dot in space and chromosomes”

  • The miracles… – ah yes, it would be fair to say that we share a cynical viewpoint on those 😉 I gather that the local candidate ‘cured’ two people from cancer. Problem is, if (& yes, I’m aware that this is an assumption on my part, but it should be possible to confirm/deny) they were both receiving conventional treatment (& many leukemias, especially, respond quite well to this), then how do we know the cure/remission was not the result of this???

  • it would be fair to say that we share a cynical viewpoint on those 😉

    It would.

    As you say, the attribution of the cure is problematic, to be polite. More than that, though. I’ve two minds as if to put what I wrote up as a post, as it’s a bit off to one side of the usual fare I offer here.

  • Hi Ron,

    I think you mean me, not Alison!

    Actually I wasn’t meaning to give you credit for the image itself (!), just indicate it where I got it from: that’s why I wrote ‘via’ rather than my usual ‘source’ or ‘from’ in the legend. I saw that you’d got from the BOCF, but doubted as if that was the original source (I’d have expected a biology dept.), but wasn’t up to tracking down the original – piked out and just wrote ‘via’ to cover it. (I linked to your article on the image, by the way – I try to do this when I can remember so that people can see the original context for themselves.)

    I see you’re a sailor – I’m a bit of a fair weather sailor, I guess, but I enjoy being off-shore.

  • Sorry, Grant,
    No problem re the image. And thanks for the link.
    I am not really a sailor, but was in a friend’s boat when this was taken. It gives me, how do you say, a certain panache I wouldn’t otherwise exhibit in my (currently) natural state in front of a computer screen.
    As for science, I have some education from university in lower division sciences (of all kinds, ‘soft’ and ‘hard’) and am bothered greatly in the way “science” is quoted and used inappropriately, as I see it. Please correct me, if necessary: science is a process, not a thing or a group of people, yes? If this is correct then we can take the next steps in determining how ‘science’ can (or more importantly, should not) be used in sentences and paragraphs that are polemical in nature.
    What do you think?
    Best wishes,

  • Sorry, Grant

    Hey, no need to apologise! 🙂

    I have a similar “current natural state”. (Nice way of putting it.)

    science is a process, not a thing or a group of people

    Right. That said, there is also data and the various “statements”—for what of a better word—hypotheses, laws, theories, etc. If you compare with ancient “science”, the emphasis is more on the process that it once was, when talking generalities over the whole of science at least. In practice, on an individual level, there are lots of little ‘spaces’ within the broad endeavour that fit different types of skills and activities. (It occurs to me that’s a point not easily seen by high school students or those outside science, and might be worth a blog post.)

    If this is correct then we can take the next steps in determining how ’science’ can (or more importantly, should not) be used in sentences and paragraphs that are polemical in nature.

    Accepting that there is bad science communication & correspondence efforts out there, in my opinion polemic approaches need caution for any subject, not just science. In particular, they’re too readily skewed into ad hominem attacks.

    Having said that, it’s worth remembering that writing for a wider audience, especially one that you have to told their attention, does want less qualifying (scientists and science wants to qualify everything with the level confidence you have in a statement) and—generally speaking—firmer language. That’s not the same thing as being polemic, though.

    Polemic approaches can be intentionally done for effect, which is a slightly different thing. (Hope you get my meaning here.)

  • Thanks for your response. As a non-scientist I have to take such discussions slowly and a step at a time. I see your point about a polemical position being potentially useful in eliciting argument leading to thoughtful conclusions, but the ad hominem impulse seems hard to contain in many folks. These are the folks that “believe” in something and are defending and attacking on its behalf. I have much trouble in listening to the argument of a professed scientist who uses the word “believe,” or any of its derivatives and synonyms.

  • For what it’s worth, when I was thinking of using a polemic style, I was thinking of John Pilger’s work, if you’re familiar with it.

    You’re right about the use of the word “believe”, but having said that as a practical matter you have to cut a little slack, too. Internet grammar/semantic pedantry can be taken too far… 🙂 All things in fair measure and all that. A lot of things are taken more harshly because readers don’t look for the intended meaning, but take the face value only. It is sloppy, though, and I think there is less excuse in writing than in casual speech. In writing you’ve got a moment to think about what you’re writing in a way that you can’t usually in casual speech.

    (Having said that it brings back memories of conversations as a student. Some scientists would pause for a long time before answering, obviously formulating their answer. That sort of conversation is accepted amongst academics (in some settings), but it wouldn’t be so acceptable in, say, a radio or TV interview!)